1. Field of the Invention
The present invention relates to an absorption refrigerator having an evaporator and an absorber formed integrally with a double tube thereof.
2. Description of the Related Art
Hitherto, an absorption refrigerator has been known which has a structure that liquid refrigerant is sprayed to the outer surface of an internal tube of a double tube which is stood erect so as to be evaporated during downward flow. Then, steam of the refrigerant is absorbed by absorbing solution sprayed to the outer surface of the outer tube. Thus, the evaporator and the absorber are formed integrally with each other. The foregoing structure enables the size to be reduced because the evaporator and the absorber are formed integrally with each other. Therefore, the overall size of the absorption refrigerator can be reduced.
However, the above-mentioned structure encounters a fact that a portion of the liquid refrigerant, which has been sprayed to the outer surface of the internal tube and which cannot be evaporated during downward flow, is as it is mixed with the absorbing solution allowed to downwards flow along the inner surface of the outer tube. Thus, a satisfactory refrigerating effect cannot be obtained. Therefore, energy is wasted. Even if the liquid refrigerant in a quantity which can be evaporated and which can be obtained theoretically from the heating area of the outer surface of the internal tube is sprayed, the structure in which the liquid refrigerant is allowed to downwards flow along the outer surface of the internal tube which is stood erect inhibits effective use of the overall outer surface of the internal tube. In the foregoing case, the overall quantity of the liquid refrigerant cannot perfectly be evaporated. If the overall quantity of the sprayed liquid refrigerant is attempted to be evaporated, a considerably large margin is required in addition to the heating area obtained theoretically. Thus, there arises a problem in that the size of the apparatus cannot be reduced.